Repsol Nabors Blowout Qugruk No. 2 SITREP No. 23

ALASKA DEPARTMENT OF ENVIRONMENTAL CONSERVATION
Division of Spill Prevention and Response
Prevention and Emergency Response Program

SITUATION REPORT
Repsol Q2 Pad Gas and Mud Release
SITREP # 23

SPILL NUMBER: 12399904601

TIME/DATE OF SPILL: Repsol reported the incident to ADEC at 10:29 a.m. on February 15, 2012.

TIME/DATE OF SITUATION REPORT: 1:30 p.m. on March 18, 2012

TYPE/AMOUNT OF PRODUCT SPILLED: Repsol estimates that approximately 42,000 gallons (1,000 barrels) of fresh-water-based drilling mud were released to the ice drilling pad and adjacent snow-covered tundra. An unknown amount of gas has been released. Drilling mud is used to lubricate the drill, control formation pressure, and remove cuttings from the bore. No oil was spilled during the release event.

INCIDENT LOCATION: Qugruk #2 pad (Q2 pad), on the Colville River Delta, approximately 18 miles northeast of Nuiqsut and approximately 150 miles southeast of Barrow (70° 27’ 19” N, 150° 44’ 52” W).

CAUSE OF SPILL: Repsol contractor Nabors Drilling was drilling an exploratory well when the drill penetrated a shallow gas pocket at a depth of 2,523 feet, resulting in a gas kick. The gas kick drove drilling mud, downhole materials and water out of the well and through the gas diverter onto the ice pad and adjacent snow-covered tundra. The gas diverter is a pipe that extends approximately 75 feet from the drilling rig toward the south edge of the pad. Additional mud was pumped into the well in an attempt to control it, but that mud was also forced out by the gas.

POTENTIAL RESPONSIBLE PARTY (PRP): Repsol E&P USA

RESPONSE ACTION: The well is plugged and controlled. The Unified Command has shifted the response management into the project phase and has demobilized the ICP in Anchorage.

The cleanup plan has been approved and is flexible so that information gained during the final delineation operations will be used to drive the cleanup actions.

The off-pad clean-up area has been divided into four zones. Delineation of two of the four zones is complete. Delineation of the final two zones will be completed today when the weather permits.

Due to the snow cover over the area it is difficult to identify the edges of the plume. When temperatures allow, a skid steer with broom and snow machines will be used to clear away the layer of clean snow which has accumulated over the top of the deposition.

Cold temperatures continue to slow the work as field crews are on a weather hold until the temperature moderates to -45°F, when they can perform hand work, and -35°F, when machines can be operated.

The temperature on site this morning was -41°F with a 10 mph wind.

SOURCE CONTROL: Mechanical well control has been achieved.

RESOURCES AFFECTED: Snow-covered tundra and ice pad. Drilling mud can affect tundra plants by changing soil pH and salinity. Brackish water produced by the well may also increase soil salinity.

FUTURE PLANS AND RECOMMENDATIONS: ADEC will monitor the site delineation and cleanup operations.